i'm going crazy over here

what can i do now to get out of this greye out update button?
if i reattach the serial interface, what are the exact steps i should do to have a functioning firmware downgraded device? what should i flash?
now i am on 5.9.4. i dont know if i am jailbroken or not, nothing installs. is there a way to test if i am jailbroken withou reconnecting the serial?
thanks!